Friday, 14 November 2008

Tricky Square Roots


The simplified expression after the square rooting the top expression seemed easy enough.

The individual terms within the square root are handled separately to obtain what is shown.

It seems to be correct and neat. Or is it?

This is a very common mistake made by many students.

It is not correct. Do take note.

Why?

The principle of indices do not permit this type of computing.

Addition of terms has to be taken as a whole (after summation or as a complete group).

The square root is actually to the power of (1/2), which is similar to that of x2.

(x + y)(x + y) = (x + y)2

[(x + y)(x+ y)]1/2 = (x + y)

Think about it.

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